[Approach] Using Simulation by Visited Matrix - O(m*n) Time and O(m*n) Space
The idea is to simulate the spiral traversal by marking the cells that have already been visited. We can use a direction array to keep track of the movement (right, down, left, up) and change direction when we hit the boundary or a visited cell.
Step By Step Implementations:
Initialize a 2D array vis[][] to keep track of visited cells.
Use direction arrays dr and dc to represent right, down, left, and up movements.
Start from the top-left cell and follow the direction arrays to visit each cell.
Change direction when encountering a boundary or a visited cell.
Continue until all cells are visited.
Output
1 2 3 4 8 12 16 15 14 13 9 5 6 7 11 10
[Expected Approach] Using Boundary Traversal - O(m*n) Time and O(1) Space
We can print the matrix in a spiral order by dividing it into loops or boundaries. We print the elements of the outer boundary first, then move inward to print the elements of the inner boundaries.
Algorithm:
Define the boundaries of the matrix with variables top, bottom, left, and right.
Print the top row from left to right and increment top.
Print the right column from top to bottom and decrement right.
Check if boundaries have crossed; if not, print the bottom row from right to left and decrement bottom.
Print the left column from bottom to top and increment left.
